This invention relates generally to round bale forming machinery and, more particularly, to an improved latching mechanism having means for sensing when the bale is ready for discharge.
An application titled "Pressure Sensing Latch for a Round Baler" having Ser. No. 283,045 and assigned to the same assignee is made copending with this one by simultaneous submission.
Many bale forming machines exist in the art. Some are designed to form bales of cotton; some form bales of paper; others form fibrous agricultural crops into wire or twine tied bales.
The U.S. Pat. No. 4,009,653 to Sacht discloses one method for forming large round bales. The Sacht machine comprises a cage-like frame having a horizontal axis and a generally cylindrical shaped paling zone. Upwardly extending machine sidewalls form the confining end surfaces of the baling zone. A plurality of serially arranged conveying elements enclose and generally define the circumferential periphery of the baling zone. Thus, the size of the baling chamber remains constant during the bale forming process. To accomplish discharge of a completed bale, the baling chamber is divided into two portions approximately along a vertically extending axis cutting plane. The rear portion of the housing is then configured to swing upward from a hinge point at the top, thereby allowing the bale to be discharged rearward.
The U.S. patent application having Ser. No. 162,372, now U.S. Pat. No. 4,319,446, and assigned to the same assignee as this application discloses bale forming means which differ somewhat from the implementation of Sacht. Two additional rollers are added to support the bottom conveyor belts. As viewed from the side the improved system shows four rollers on which a plurality of laterally spaced belts are trained. The second and third rollers (which are respectively in the forward and aft portions of the conveyor midsection) and the fourth roller (which is at the rear of the machine) are disposed to be generally on the cylindrical periphery of the baling zone. The first roller is in front of and somewhat below the plane containing the axis of the third roller. The invention improves on Sacht in two ways. First, the vertical dimension of the entrance throat is enlarged. This allows the baler to operate in a heavier stand of hay without becoming clogged. Second, by lowering the placement of the front roller, a pickup reel of similar diameter can be used. This permits the flow of hay being picked up from the window to pass into the baling zone without undergoing abrupt changes in direction. The laterally spaced conveyor belts accept the crop material being passed on from the pickup reel and frictionally engage the crop strands to provide inward directed pressure to carry them into the baling zone.
U.S. Pat. No. 4,246,743 is representative of signaling means which use a moving take-up means to signal when the bale has reached a predetermined size. Such devices are not sensitive to pressures intitially built up within a bale and then asserted against the walls of the bale cavity.
This invention is shown in conjunction with a baler having a bottom conveyor member for receiving agricultural material which is constructed similar to that disclosed in the U.S. patent application having Ser. No. 162,372. This is done for exemplary purposes only. The latching mechanism will function reliably with any baler having a tailgate on which pressure is applied by a bale.
The latching mechanism provides a simple means of sensing bale density. The profile of the latch-action is matched to the forces tending to open the gate through which a completed bale is discharged.